A court in Russia has jailed a Russian man for fighting against Kremlin-backed separatists in Ukraine's eastern region of Donetsk.

The Russian Investigative Committee said on August 30 that a court in the Kirov region found a 24-year-old local resident guilty of fighting as a mercenary for a foreign country and sentenced him to 2 1/2 years in jail.

The man, whose identity was not disclosed, was detained after returning to Russia's Kirov region in September 2015. He had been fighting alongside Ukrainian armed forces against pro-Russian separatists for more than six months.

Fighting between Ukrainian government forces and Russia-backed separatists in Ukraine's eastern regions of Luhansk and Donetsk has killed more than 9,500 people since April 2014.

There have been numerous reports that many volunteers and mercenaries from former Soviet republics are fighting on both sides of the conflict.